Many different crop cutting systems includes a sickle apparatus comprising a frame structure arranged for forward travel over ground having a standing crop thereon, a cutter bar secured to the frame structure and extending transversely across a front end of said frame structure, a plurality of knife guards mounted in spaced relation along said cutter bar and projecting forwardly therefrom where each of said guards has a ledger surface with opposed side edges thereof arranged to provide first and second shearing edges, at least one sickle bar mounted in transversely extending position driven for reciprocating movement relative to said knife guards and having a plurality of knife blades mounted thereon for movement therewith with each of the knife blades having two side cutting edges which cooperate with said shearing edges of said knife guards and a drive system for driving said at least one sickle bar through repeated cycles of reciprocating movement from start-up through to a shut-down. Many arrangements of this type are shown in the prior art.